全文获取类型
收费全文 | 1199篇 |
免费 | 98篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 93篇 |
妇产科学 | 65篇 |
基础医学 | 124篇 |
口腔科学 | 30篇 |
临床医学 | 111篇 |
内科学 | 226篇 |
皮肤病学 | 55篇 |
神经病学 | 102篇 |
特种医学 | 31篇 |
外科学 | 102篇 |
综合类 | 12篇 |
一般理论 | 2篇 |
预防医学 | 63篇 |
眼科学 | 78篇 |
药学 | 112篇 |
中国医学 | 5篇 |
肿瘤学 | 84篇 |
出版年
2024年 | 1篇 |
2023年 | 23篇 |
2022年 | 62篇 |
2021年 | 72篇 |
2020年 | 65篇 |
2019年 | 76篇 |
2018年 | 84篇 |
2017年 | 60篇 |
2016年 | 87篇 |
2015年 | 55篇 |
2014年 | 90篇 |
2013年 | 91篇 |
2012年 | 98篇 |
2011年 | 100篇 |
2010年 | 47篇 |
2009年 | 45篇 |
2008年 | 62篇 |
2007年 | 62篇 |
2006年 | 45篇 |
2005年 | 27篇 |
2004年 | 15篇 |
2003年 | 9篇 |
2002年 | 7篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1998年 | 1篇 |
1994年 | 1篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1988年 | 6篇 |
1987年 | 1篇 |
1966年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有1301条查询结果,搜索用时 0 毫秒
91.
Paula W. Rushton Ben W. Mortenson Pooja Viswanathan Rosalie H. Wang William C. Miller Laura Hurd Clarke 《Disability and rehabilitation. Assistive technology》2017,12(7):740-746
Purpose: Long-term care (LTC) residents with cognitive impairments frequently experience limited mobility and participation in preferred activities. Although a power wheelchair could mitigate some of these mobility and participation challenges, this technology is often not prescribed for this population due to safety concerns. An intelligent power wheelchair (IPW) system represents a potential intervention that could help to overcome these concerns. The purpose of this study was to explore a) how residents experienced an IPW that used three different modes of control and b) what perceived effect the IPW would have on their daily lives.Materials and methods: We interviewed 10 LTC residents with mild or moderate cognitive impairment twice, once before and once after testing the IPW. Interviews were conducted using a semi-structured interview guide, audio recorded and transcribed verbatim for thematic analyses.Results: Our analyses identified three overarching themes: (1) the difference an IPW would make, (2) the potential impact of the IPW on others and (3) IPW-related concerns.Conclusions: Findings from this study confirm the need for and potential benefits of IPW use in LTC. Future studies will involve testing IPW improvements based on feedback and insights from this study.
- Implications for rehabilitation
Intelligent power wheelchairs may enhance participation and improve safety and feelings of well-being for long-term care residents with cognitive impairments.
Intelligent power wheelchairs could potentially have an equally positive impact on facility staff, other residents, and family and friends by decreasing workload and increasing safety.
92.
Pooja Bhardwaj Elizabeth Ziegler Kelli L. Palmer 《Antimicrobial agents and chemotherapy》2016,60(4):2209-2221
Chlorhexidine is a bisbiguanide antiseptic used for infection control. Vancomycin-resistant E. faecium (VREfm) is among the leading causes of hospital-acquired infections. VREfm may be exposed to chlorhexidine at supra- and subinhibitory concentrations as a result of chlorhexidine bathing and chlorhexidine-impregnated central venous catheter use. We used RNA sequencing to investigate how VREfm responds to chlorhexidine gluconate exposure. Among the 35 genes upregulated ≥10-fold after 15 min of exposure to the MIC of chlorhexidine gluconate were those encoding VanA-type vancomycin resistance (vanHAX) and those associated with reduced daptomycin susceptibility (liaXYZ). We confirmed that vanA upregulation was not strain or species specific by querying other VanA-type VRE. VanB-type genes were not induced. The vanH promoter was found to be responsive to subinhibitory chlorhexidine gluconate in VREfm, as was production of the VanX protein. Using vanH reporter experiments with Bacillus subtilis and deletion analysis in VREfm, we found that this phenomenon is VanR dependent. Deletion of vanR did not result in increased chlorhexidine susceptibility, demonstrating that vanHAX induction is not protective against chlorhexidine. As expected, VanA-type VRE is more susceptible to ceftriaxone in the presence of sub-MIC chlorhexidine. Unexpectedly, VREfm is also more susceptible to vancomycin in the presence of subinhibitory chlorhexidine, suggesting that chlorhexidine-induced gene expression changes lead to additional alterations in cell wall synthesis. We conclude that chlorhexidine induces expression of VanA-type vancomycin resistance genes and genes associated with daptomycin nonsusceptibility. Overall, our results indicate that the impacts of subinhibitory chlorhexidine exposure on hospital-associated pathogens should be further investigated in laboratory studies. 相似文献
93.
94.
Sood P Idris NF Cole S Grayson B Neill JC Young AM 《Journal of psychopharmacology (Oxford, England)》2011,25(6):792-800
This study investigated the effects of the dopamine D(4) receptor agonist, PD168077, on recognition memory using a novel object recognition task, which detects disruption and improvement of recognition memory in rats by measuring their ability to discriminate between familiar and novel objects. When acquisition and test were 6?h apart (experiment 1), control rats failed to discriminate between familiar and novel objects at test. Rats given low doses of PD168077 (0.3; 1.0?mg/kg) also failed to discriminate between the objects, while rats given higher doses (3.0; 10.0?mg/kg) explored the novel object more than the familiar object, indicating retained memory of the familiar object. Thus, at higher doses, PD168077 improved recognition memory in rats. Experiment 2 tested whether PD168077 would attenuate deficits in novel object recognition induced by sub-chronic phencyclidine. Testing was 1?min after acquisition, such that vehicle pre-treated rats differentiated between the novel and familiar objects: however, sub-chronic phencyclidine-treated rats failed to discriminate between the two, indicating disruption of recognition memory. PD168077 (10?mg/kg) restored the ability of phencyclidine-treated rats to differentiate between the novel and familiar objects, indicating improved recognition memory. The results suggest that D(4) receptor activation can improve cognitive dysfunction in an animal model relevant to schizophrenia. 相似文献
95.
Divya Sagar Catherine Foss Rasha El Baz Martin G. Pomper Zafar K. Khan Pooja Jain 《Journal of neuroimmune pharmacology》2012,7(1):74-94
Although the central nervous system (CNS) is considered to be an immunoprivileged site, it is susceptible to a host of autoimmune
as well as neuroinflammatory disorders owing to recruitment of immune cells across the blood–brain barrier into perivascular
and parenchymal spaces. Dendritic cells (DCs), which are involved in both primary and secondary immune responses, are the
most potent immune cells in terms of antigen uptake and processing as well as presentation to T cells. In light of the emerging
importance of DC traficking into the CNS, these cells represent good candidates for targeted immunotherapy against various
neuroinflammatory diseases. This review focuses on potential physiological events and receptor interactions between DCs and
the microvascular endothelial cells of the brain as they transmigrate into the CNS during degeneration and injury. A clear
understanding of the underlying mechanisms involved in DC migration may advance the development of new therapies that manipulate
these mechanistic properties via pharmacologic intervention. Furthermore, therapeutic validation should be in concurrence
with the molecular imaging techniques that can detect migration of these cells in vivo. Since the use of noninvasive methods
to image migration of DCs into CNS has barely been explored, we highlighted potential molecular imaging techniques to achieve
this goal. Overall, information provided will bring this important leukocyte population to the forefront as key players in
the immune cascade in the light of the emerging contribution of DCs to CNS health and disease. 相似文献
96.
97.
The human immune system is under constant challenge from many viruses, some of which the body is successfully able to clear. Other viruses have evolved to escape the host immune responses and thus persist, leading to the development of chronic diseases. Dendritic cells are professional antigen-presenting cells that play a major role in both innate and adaptive immunity against different pathogens. This review focuses on the interaction of different chronic viruses with dendritic cells and the viruses' ability to exploit this critical cell type to their advantage so as to establish persistence within the host. 相似文献
98.
Liu X Mishra P Yu S Beckmann J Wendland M Kocks J Seth S Hoffmann K Hoffmann M Kremmer E Förster R Worbs T 《European journal of immunology》2011,41(3):611-623
Deficiency of transplant recipients for the chemokine receptor CCR7 was originally described to slightly increase the survival time of vascularized solid organ grafts, probably due to a reduced priming of alloreactive T cells. Using a model of allotolerance induction by donor-specific splenocyte transfusion (DST) in combination with anti-CD40L mAb-mediated costimulation blockade (CSB), we show here a striking failure of CCR7-deficient (CCR7(-/-) ) recipients to tolerate cardiac allografts. Furthermore, in addition to the recently described lack of Treg, CCR7(-/-) mice were found to harbor significantly reduced numbers of plasmacytoid dendritic cells (pDCs) within peripheral as well as mesenteric lymph nodes (LNs), but not the bone marrow or spleen. pDCs had previously been suggested to function as tolerogenic APC during allograft transplantation, and a single transfer of syngeneic WT pDCs, but not conventional DCs, was indeed sufficient to rescue graft survival in DST+CSB-treated CCR7(-/-) recipients in a dose-dependent manner. We therefore conclude that the nearly complete absence of pDCs within LNs of CCR7(-/-) mice prevents the successful induction of DST+CSB-mediated allotolerance, leading to the observed acute rejection of cardiac allografts under tolerizing conditions. 相似文献
99.
Rachel J Wetzsteon Justine Shults Babette S Zemel Pooja U Gupta Jon M Burnham Rita M Herskovitz Krista M Howard Mary B Leonard 《Journal of bone and mineral research》2009,24(3):503-513
Glucocorticoid (GC) effects on skeletal development have not been established. The objective of this pQCT study was to assess volumetric BMD (vBMD) and cortical dimensions in childhood steroid‐sensitive nephrotic syndrome (SSNS), a disorder with minimal independent deleterious skeletal effects. Tibia pQCT was used to assess trabecular and cortical vBMD, cortical dimensions, and muscle area in 55 SSNS (age, 5–19 yr) and >650 control participants. Race‐, sex‐, and age‐, or tibia length‐specific Z‐scores were generated for pQCT outcomes. Bone biomarkers included bone‐specific alkaline phosphatase and urinary deoxypyridinoline. SSNS participants had lower height Z‐scores (p < 0.0001) compared with controls. In SSNS, Z‐scores for cortical area were greater (+0.37; 95% CI = 0.09, 0.66; p = 0.01), for cortical vBMD were greater (+1.17; 95% CI = 0.89, 1.45; p < 0.0001), and for trabecular vBMD were lower (?0.60; 95% CI, = ?0.89, ?0.31; p < 0.0001) compared with controls. Muscle area (+0.34; 95% CI = 0.08, 0.61; p = 0.01) and fat area (+0.56; 95% CI = 0.27, 0.84; p < 0.001) Z‐scores were greater in SSNS, and adjustment for muscle area eliminated the greater cortical area in SSNS. Bone formation and resorption biomarkers were significantly and inversely associated with cortical vBMD in SSNS and controls and were significantly lower in the 34 SSNS participants taking GCs at the time of the study compared with controls. In conclusion, GCs in SSNS were associated with significantly greater cortical vBMD and cortical area and lower trabecular vBMD, with evidence of low bone turnover. Lower bone biomarkers were associated with greater cortical vBMD. Studies are needed to determine the fracture implications of these varied effects. 相似文献
100.
Yogita Dalla Nirmal Singh Amteshwar Singh Jaggi Dhandeep Singh Pooja Ghulati 《Indian journal of pharmacology》2009,41(6):262-267